Question

If a car is moving with a vilocity of 54 kam/h appling brake for 10sec how far body will cover​

Answer 1

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ANSWER:

• Distance covered by the body = 75 m

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GIVEN:

• Initial velocity = 54 kmph

• Time = 10 s

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TO FIND:

• Distance covered by the body

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CONVERSION:

• 1 kmph = 1000/3600 m/s = 5/18 m/s

• 54 kmph = 54 × 5/18 = 5 × 3 = 15 m/s

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EXPLANATION:

$\boxed{ \large {\bold{ v = u + at}}}$

v = 0

Because at last the body comes to rest

u = 15 m/s

t = 10 s

0 = 15 + a(10)

10 a = - 15

a = - 1.5 m/s²

$\boxed{ \large {\bold{ s = ut + \frac{1}{2} a {t}^{2} }}}$

s = 15(10) + 1/2(- 1.5)(10²)

s = 150 + 1/2(- 1.5)(100)

s = 150 + (- 1.5)(50)

s = 150 - 75

s = 75 m

HENCE THE BODY TRAVELS 75 m BEFORE IT COMES TO REST.

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